Technical Field
This disclosure relates to computer networking More specifically, this disclosure relates to flexible interconnection of scalable systems integrated using optical networks for datacenters.
Related Art
Datacenters (DCs) are considered as the brain of the Internet—storing repositories of easily accessible information. The architecture of datacenters has gathered significant attention in the recent years. The classical model of providing top-of-the-rack switches in a hierarchical fashion and interconnecting these to an edge router is well deployed. This architecture has two limitations: (1) providing scalability of the DC interconnection fabric, and (2) scaling a protocol to support the vast number of systems (servers, storage). With the surge of social media, explosion of video content, latency sensitive applications being consumed by mobile backhaul and the general thought of gigabit-to-the-home, there is a tremendous stress on the data-center infrastructure. The DC must now scale to meet the requirements of applications, some of which interact within the data-center environment as well as have latency tolerance that causes severe testing of service provider service level agreements (SLAs).
The common methodology of data-center design is to deploy a large number of commonly available off-the-shelf computing elements interconnected across a redundant networking fabric. To meet the scalability of the networking fabric, the key-requirement is to be able to provision 10s of 1000s of servers in an efficient and fault-tolerant mechanism within the DC. Bandwidth bottlenecks are created by traditional hierarchical designs and it becomes difficult to meet the requirements of full bisection bandwidth as the number of servers increases.
A second problem that arises from this scalability is to support protocol within the DC environment. The common Layer 2-3 protocols of Ethernet and IP do not scale in such environments. Ethernet has issues of scalability when used in its conventional form of Ethernet bridges. Internet Protocol (IP) scales, but the processing of IP packets at each branch and leaf in a hierarchical tree within the DC environment causes unacceptable processing delays and is expensive.